One of the constituents of the vitamin B complex, folic acid derives its name from the fact that it is found in many green leaves, including spinach and grass. It has also been obtained from liver, kidney and yeasts. It has proved to be of value in the treatment of macrocytic anaemias (see ANAEMIA), particularly those associated with SPRUE and nutritional deﬁciencies.
In order to prevent NEURAL TUBE defects and cleft lip or palate (see CLEFT PALATE), all women planning to become pregnant should be advised to have a diet rich in folic acid in the months before conception until 13 weeks’ gestation, or to take folic acid tablets.
Recent research has suggested that adequate levels of folic acid can prevent the build-up of homocysteine, a compound in the blood closely associated with heart attacks and strokes. It has been suggested that the oﬃcial recommendation of 200 micrograms a day in the diet should be doubled. (See APPENDIX 5: VITAMINS.)